CN103399407A - Method for shaping round beam into spot beam and annular beam - Google Patents

Abstract

The invention relates to the field of non-image optics, provides a method for shaping a round beam into a spot beam and an annular beam, and aims to lower the complexity of the installing and debugging of the receiving system of an inter-satellite optical communication terminal and simplify the optical system structure of the inter-satellite optical communication terminal. The method comprises the following steps: (1) determining the diameter D0 of an incident beam; (2) determining the calibre D of a communication beam; (3) building a one to one correspondence relationship for the communication beam; (4) calculating the ray declination angle of the communication beam; (5) determining the radial phase distribution expression of the communication part of a complex function element; (6) determining the radial outline of the communication part of the complex function element; (7) building a one to one correspondence relationship for a tracking beam; (8) calculating the ray declination angle of the tracking beam; (9) determining the radial phase distribution expression of the tracking part of the complex function element; (10) determining the radial outline of the tracking part of the complex function element. The method is applicable to the field of non-imaging optics.

Description

A kind of be used to realizing that circular light beam is shaped as the method for an annular beam

Technical field

The present invention relates to the nonimaging optics field, relate in particular to a kind of for circular light beam being shaped as the method for an annular beam.

Background technology

The receiving system of satellite optical communication terminal mainly comprises follows the tracks of detection system and communication system.Typical satellite optical communication terminal optical system mainly is comprised of optical antenna (1), spectroscope (2), communication focus lens group (3), communication detecting device (4), tracking focus lens group (5) and tracking detector (6), as shown in Figure 2.When this terminal receiving optical signals, incident beam is after the contracting bundle without burnt optical antenna (1), and incident light is divided to following the tracks of light path and the light path of communicating by letter.Focus on tracking detector (6) through following the tracks of focus lens group (5) after front portion light is reflected by spectroscope (2), be used for aiming at, catching and follow the tracks of.Another part directly sees through spectroscope (2) and focuses on communication detecting device (4) through communication focus lens group (3), is used for communication.As shown in Figure 2, two light paths (tracking section and communications portion) are arranged in receiving system, cause the terminal optical system structure too complicated, increased the complexity of debuging of system, and terminal volume is excessive, be unfavorable for that terminal is toward the miniaturization development.

Summary of the invention

The present invention is the complexity of debuging that will reduce satellite optical communication terminal receiving system, simplifies the terminal optical system structure, and provides a kind of be used to realizing that circular light beam is shaped as the method for an annular beam.

Be used for realizing that the method that circular light beam is shaped as an annular beam realizes according to the following steps:

(1) determine the diameter D of incident beam ₀, the inner and outer ring diameter D of annular beam ₁, D ₂Spacing L with complex function element and 4 quadrant detector: if the optical antenna bore is d, its enlargement ratio is T, D ₀=d/T;

(2) determine the bore D of communication beam: if Communication ray power accounts for the η of incident optical power,

$D=\sqrt{\mathrm{\η}}{D}_0$

(3) set up the one-to-one relationship of communication beam: on the complex function component side from distance beam center r ₁The light that place sends incides test surface center, wherein 0≤r ₁≤ D;

(4) calculate the light drift angle of communication beam:, by geometric relationship, can determine

$\sin \mathrm{\β}=\frac{r_1}{L}$

(5) determine the radial phase distribution and expression formula of complex function element communications portion: by the relation between iconal and light drift angle, can be obtained

$\frac{{\mathrm{d\&phi;}}_1\left(r_1\right)}{{\mathrm{<figure-callout\; id="1"\; label="dr"\; filenames="HDA00003661434800021.png,HDA00003661434800022.png"\; state="\{\{state\}\}">dr</figure-callout>}}_1}=-\sin \mathrm{\&beta;}$

To the following formula integration, the radial phase that obtains complex function element communications portion distributes, 0≤r in formula ₁≤ D;

(6) determine the radial contour of complex function element communications portion: the radial contour that can be obtained complex function element communications portion by the relation of phase place and component thickness

${\mathrm{\&phi;}}_1\left(r_1\right)=2\mathrm{\&pi;}\&CenterDot;\frac{{\mathrm{nz}}_1\left(r_1\right)}{\mathrm{\&lambda;}}$

In formula, n is the refractive index of complex function element, and λ is light beam wavelength, and 0≤r ₁≤ D;

(7) set up the one-to-one relationship of following the tracks of light beam;

(8) calculate the light drift angle of communication beam:, by geometric relationship, can determine

$\sin \mathrm{\&alpha;}=\frac{r_3-r_2}{L}$

(9) determine the radial phase distribution and expression formula of complex function element tracks part: by the relation between iconal and light drift angle, can be obtained

$\frac{{\mathrm{d\&phi;}}_2\left(r_2\right)}{{\mathrm{<figure-callout\; id="2"\; label="dr"\; filenames="HDA00003661434800021.png"\; state="\{\{state\}\}">dr</figure-callout>}}_2}=\sin \mathrm{\&alpha;}$

To the following formula integration, the radial phase that obtains complex function element tracks part distributes, D≤r in formula ₂≤ D ₀

(10) determine the radial contour of complex function element tracks part: the radial contour that can be obtained complex function element tracks part by the relation of phase place and component thickness

${\mathrm{\&phi;}}_2\left(r_2\right)=2\mathrm{\&pi;}\&CenterDot;\frac{{\mathrm{nz}}_2\left(r_2\right)}{\mathrm{\&lambda;}}$

In formula, n is the refractive index of complex function element, and λ is light beam wavelength, and D≤r ₂≤ D ₀,

Namely completed the design that utilizes Ray-tracing Method to realize the complex function element, realized that circular light beam is shaped as an annular beam.

The invention effect:

The present invention utilizes Ray-tracing Method to realize the design of complex function element, the complex function element can be realized circular light beam is shaped as an annular beam, tracking detector and signal sensor are incorporated on same optical axis, reach and reduce terminal volume with this, improve purposes such as following the tracks of degree of stability, this is significant to the miniaturization of satellite optical communication terminal.

For reducing the complexity of debuging of optical subsystem, simplify the terminal optical system structure, can add the complex function element system is optimized.The optical system of composite received system mainly is comprised of optical antenna (1), communication focus lens group (3), communication detecting device (4), complex function element (7) and four-quadrant tracking detector (8), as shown in Figure 3.When this terminal receiving optical signals, incident beam after the contracting bundle without burnt optical antenna (1), is divided into two parts (tracking section and communications portion) by complex function element (7).Front portion light distributes after by the complex function component shaping ringwise on four-quadrant tracking detector (8), be used for aiming at, catching and follow the tracks of.Another part is focused on the center drilling place of four-quadrant tracking detector (8) by complex function element (7), it is not subjected to blocking of detector, finally by communication focus lens group (3), focuses on communication detecting device (4), is used for communication.The central area of 4 quadrant detector is through hole, can allow focused beam freely to pass through, and Fig. 4 has shown the distribution of some ring-type hot spots on 4 quadrant detector.

The complex function element is realized circular light beam is shaped as an annular beam, tracking detector and signal sensor are incorporated on same optical axis, reach and reduce terminal volume with this, improve purposes such as following the tracks of degree of stability, this is significant to the miniaturization of satellite optical communication terminal.

Description of drawings

Fig. 1 is process flow diagram of the present invention;

Fig. 2 is typical optical system configuration composition in background technology;

Fig. 3 is the optical system configuration composition of composite received system in background technology;

Fig. 4 is composite received system left view in background technology; Wherein, a is ring, and b is a little, and c is four limit detectors;

Fig. 5 is that in embodiment one, Gauss beam reshaping is the structural drawing of an annular beam;

Fig. 6 is that in embodiment four, Gauss beam reshaping is the schematic diagram of an annular beam;

Fig. 7 is iconal in embodiment one and the graph of a relation between the light drift angle.

Embodiment

Embodiment one: in conjunction with Fig. 1～Fig. 7, present embodiment is described, present embodiment a kind of be used to realizing that the method that circular light beam is shaped as an annular beam realizes according to the following steps:

As follows for the method for designing concrete steps that circular light beam are shaped as annular beam:

(1), as Fig. 5, determine the diameter D of incident beam ₀, the inner and outer ring diameter D of annular beam ₁, D ₂, and the spacing L of complex function element and 4 quadrant detector: if the optical antenna bore is respectively d, its enlargement ratio is T, D ₀=d/T;

(2), as Fig. 5, determine the bore D of communication beam: if Communication ray power accounts for the η of incident optical power,

$D=\sqrt{\mathrm{\&eta;}}{D}_0$

(3) set up the one-to-one relationship of communication beam: as Fig. 6, on the complex function component side from distance beam center r ₁The light that place sends incides test surface center, wherein 0≤r ₁≤ D;

(4) calculate the light drift angle of communication beam:, by geometric relationship, can determine

$\sin \mathrm{\&beta;}=\frac{r_1}{L}$

(5) determine the radial phase distribution and expression formula of complex function element communications portion:, as Fig. 7,, by the relation between iconal and light drift angle and in conjunction with Fig. 6, can obtain

$\frac{{\mathrm{d\&phi;}}_1\left(r_1\right)}{{\mathrm{<figure-callout\; id="1"\; label="dr"\; filenames="HDA00003661434800021.png,HDA00003661434800022.png"\; state="\{\{state\}\}">dr</figure-callout>}}_1}=-\sin \mathrm{\&beta;}$

To the following formula integration, the radial phase that obtains complex function element communications portion distributes, 0≤r in formula ₁≤ D;

(6) determine the radial contour of complex function element communications portion: the radial contour that can be obtained complex function element communications portion by the relation of phase place and component thickness

${\mathrm{\&phi;}}_1\left(r_1\right)=2\mathrm{\&pi;}\&CenterDot;\frac{{\mathrm{nz}}_1\left(r_1\right)}{\mathrm{\&lambda;}}$

In formula, n is the refractive index of complex function element, and λ is light beam wavelength, and 0≤r ₁≤ D;

(7) set up the one-to-one relationship of following the tracks of light beam;

(8) calculate the light drift angle of communication beam:, by geometric relationship, can determine

$\sin \mathrm{\&alpha;}=\frac{r_3-r_2}{L}$

(9) determine the radial phase distribution and expression formula of complex function element tracks part:, as Fig. 7,, by the relation between iconal and light drift angle and in conjunction with Fig. 6, can obtain

$\frac{{\mathrm{d\&phi;}}_2\left(r_2\right)}{{\mathrm{<figure-callout\; id="2"\; label="dr"\; filenames="HDA00003661434800021.png"\; state="\{\{state\}\}">dr</figure-callout>}}_2}=\sin \mathrm{\&alpha;}$

To the following formula integration, the radial phase that obtains complex function element tracks part distributes, D≤r in formula ₂≤ D ₀

(10) determine the radial contour of complex function element tracks part: the radial contour that can be obtained complex function element tracks part by the relation of phase place and component thickness

${\mathrm{\&phi;}}_2\left(r_2\right)=2\mathrm{\&pi;}\&CenterDot;\frac{{\mathrm{nz}}_2\left(r_2\right)}{\mathrm{\&lambda;}}$

In formula, n is the refractive index of complex function element, and λ is light beam wavelength, and D≤r ₂≤ D ₀

The present embodiment effect:

The surface of the element of designing by the method for designing described in present embodiment is continuous surface, helps processing, has increased practicality.

The present invention utilizes Ray-tracing Method to realize the design of complex function element, the complex function element can be realized circular light beam is shaped as an annular beam, tracking detector and signal sensor are incorporated on same optical axis, reach and reduce terminal volume with this, improve purposes such as following the tracks of degree of stability, this is significant to the miniaturization of satellite optical communication terminal.

For reducing the complexity of debuging of optical subsystem, simplify the terminal optical system structure, can add the complex function element system is optimized.The optical system of composite received system mainly is comprised of optical antenna (1), communication focus lens group (3), communication detecting device (4), complex function element (7) and four-quadrant tracking detector (8), as shown in Figure 3.When this terminal receiving optical signals, incident beam after the contracting bundle without burnt optical antenna (1), is divided into two parts (tracking section and communications portion) by complex function element (7).Front portion light distributes after by the complex function component shaping ringwise on four-quadrant tracking detector (8), be used for aiming at, catching and follow the tracks of.Another part is focused on the center drilling place of four-quadrant tracking detector (8) by complex function element (7), it is not subjected to blocking of detector, finally by communication focus lens group (3), focuses on communication detecting device (4), is used for communication.The central area of 4 quadrant detector is through hole, can allow focused beam freely to pass through, and Fig. 4 has shown the distribution of some ring-type hot spots on 4 quadrant detector.

The complex function element is realized circular light beam is shaped as an annular beam, tracking detector and signal sensor are incorporated on same optical axis, reach and reduce terminal volume with this, improve purposes such as following the tracks of degree of stability, this is significant to the miniaturization of satellite optical communication terminal.

Embodiment two: what present embodiment was different from embodiment one is: D described in step (1) ₁And D ₂Main relevant with the size of 4 quadrant detector, should guarantee that they are all in the investigative range of detector; Get L 〉=2D ₀Other step and parameter are identical with embodiment one.

Embodiment three: what present embodiment was different from embodiment one or two is: 0＜η＜1 in step (2), it is determined by parameters such as incident optical power and the bit error rates.Other step and parameter are identical with embodiment one or two.

Embodiment four: what present embodiment was different from one of embodiment one to three is: set up the one-to-one relationship of following the tracks of light beam in step (7) and be specially: on the complex function component side from distance beam center r ₂The light that place sends incides test surface center r ₃Place, wherein D≤r ₂≤ D ₀, D ₁≤ r ₃≤ D ₂, and meet relation

Other step and parameter are identical with one of embodiment one to three.

Embodiment five: what present embodiment was different from one of embodiment one to four is: in step (10), the complex function element comprises communication tracking two parts.Other step and parameter are identical with one of embodiment one to four.

Claims (5)

1. one kind is used for realizing that circular light beam is shaped as the method for an annular beam, it is characterized in that be used to realizing that the method that circular light beam is shaped as an annular beam realizes according to the following steps:

(1) determine the diameter D of incident beam ₀, the inner and outer ring diameter D of annular beam ₁, D ₂Spacing L with complex function element and 4 quadrant detector: if the optical antenna bore is d, its enlargement ratio is T, D ₀=d/T;

(2) determine the bore D of communication beam: if Communication ray power accounts for the η of incident optical power,

$D=\sqrt{\mathrm{\&eta;}}{D}_0;$

(3) set up the one-to-one relationship of communication beam: on the complex function component side from distance beam center r ₁The light that place sends incides test surface center, wherein 0≤r ₁≤ D;

(4) calculate the light drift angle of communication beam:, by geometric relationship, can determine

$\sin \mathrm{\&beta;}=\frac{r_1}{L};$

(5) determine the radial phase distribution and expression formula of complex function element communications portion: by the relation between iconal and light drift angle, can be obtained

$\frac{{\mathrm{d\&phi;}}_1\left(r_1\right)}{{\mathrm{dr}}_1}=-\sin \mathrm{\&beta;}$

To the following formula integration, the radial phase that obtains complex function element communications portion distributes, 0≤r in formula ₁≤ D;

(6) determine the radial contour of complex function element communications portion: the radial contour that can be obtained complex function element communications portion by the relation of phase place and component thickness

${\mathrm{\&phi;}}_1\left(r_1\right)=2\mathrm{\&pi;}\&CenterDot;\frac{{\mathrm{nz}}_1\left(r_1\right)}{\mathrm{\&lambda;}}$

In formula, n is the refractive index of complex function element, and λ is light beam wavelength, and 0≤r ₁≤ D;

(7) set up the one-to-one relationship of following the tracks of light beam;

(8) calculate the light drift angle of communication beam:, by geometric relationship, can determine

$\sin \mathrm{\&alpha;}=\frac{r_3-r_2}{L};$

(9) determine the radial phase distribution and expression formula of complex function element tracks part: by the relation between iconal and light drift angle, can be obtained

$\frac{{\mathrm{d\&phi;}}_2\left(r_2\right)}{{\mathrm{dr}}_2}=\sin \mathrm{\&alpha;}$

To the following formula integration, the radial phase that obtains complex function element tracks part distributes, D≤r in formula ₂≤ D ₀

(10) determine the radial contour of complex function element tracks part: the radial contour that can be obtained complex function element tracks part by the relation of phase place and component thickness

${\mathrm{\&phi;}}_2\left(r_2\right)=2\mathrm{\&pi;}\&CenterDot;\frac{{\mathrm{nz}}_2\left(r_2\right)}{\mathrm{\&lambda;}}$

In formula, n is the refractive index of complex function element, and λ is light beam wavelength, and D≤r ₂≤ D ₀,

Namely completed the design that utilizes Ray-tracing Method to realize the complex function element, realized that circular light beam is shaped as an annular beam.

2. according to claim 1 a kind of be used to realizing that circular light beam is shaped as the method for an annular beam, it is characterized in that D described in step (1) ₁And D ₂Main relevant with the size of 4 quadrant detector, should guarantee that they are all in the investigative range of detector; Get L 〉=2D ₀

3. according to claim 1ly a kind ofly be used to realizing that circular light beam is shaped as the method for an annular beam, it is characterized in that 0＜η＜1 in step (2), it is determined by parameters such as incident optical power and the bit error rates.

4. according to claim 1 a kind of be used to realizing that circular light beam is shaped as the method for an annular beam, it is characterized in that in step (7) that setting up the one-to-one relationship of following the tracks of light beam is specially: on the complex function component side from distance beam center r ₂The light that place sends incides test surface center r ₃Place, wherein D≤r ₂≤ D ₀, D ₁≤ r ₃≤ D ₂, and meet relation

$r_3=D_1+\frac{D_2-D_1}{D_0-D}\&CenterDot;(r_2-D).$

5. according to claim 1 a kind of be used to realizing that circular light beam is shaped as the method for an annular beam, it is characterized in that in step (10), the complex function element comprises communication tracking two parts.

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